I'm running :
Forge 1.12.2
Windows 11

Here's the crash report :
java.lang.NullPointerException: Unexpected error
at forestry.book.BookLoader.getResource(BookLoader.java:130)
at forestry.book.BookLoader.fromJson(BookLoader.java:205)
at forestry.book.BookLoader.loadEntries(BookLoader.java:194)
at forestry.book.BookLoader.lambda$loadCategory$2(BookLoader.java:168)
at java.lang.Iterable.forEach(Unknown Source)
at forestry.book.BookLoader.loadCategory(BookLoader.java:168)
at forestry.book.BookLoader.loadBook(BookLoader.java:114)
at forestry.book.items.ItemForesterBook.getGui(ItemForesterBook.java:39)
at forestry.core.gui.GuiHandler.getClientGuiElement(GuiHandler.java:93)
at net.minecraftforge.fml.common.network.NetworkRegistry.getLocalGuiContainer(NetworkRegistry.java:276)
at net.minecraftforge.fml.common.network.internal.FMLNetworkHandler.openGui(FMLNetworkHandler.java:111)
at net.minecraft.entity.player.EntityPlayer.openGui(EntityPlayer.java:2550)
at forestry.core.gui.GuiHandler.openGui(GuiHandler.java:47)
at forestry.core.gui.GuiHandler.openGui(GuiHandler.java:42)
at forestry.core.items.ItemWithGui.openGui(ItemWithGui.java:41)
at forestry.book.items.ItemForesterBook.func_77659_a(ItemForesterBook.java:30)
at net.minecraft.item.ItemStack.func_77957_a(ItemStack.java:217)
at net.minecraft.client.multiplayer.PlayerControllerMP.func_187101_a(PlayerControllerMP.java:511)
at net.minecraft.client.Minecraft.func_147121_ag(Minecraft.java:1597)
at net.minecraft.client.Minecraft.func_184117_aA(Minecraft.java:2254)
at net.minecraft.client.Minecraft.func_184118_az(Minecraft.java:2020)
at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1808)
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1098)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:398)
at net.minecraft.client.main.Main.main(SourceFile:123)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

Stacktrace:
at forestry.book.BookLoader.getResource(BookLoader.java:130)
at forestry.book.BookLoader.fromJson(BookLoader.java:205)
at forestry.book.BookLoader.loadEntries(BookLoader.java:194)
at forestry.book.BookLoader.lambda$loadCategory$2(BookLoader.java:168)
at java.lang.Iterable.forEach(Unknown Source)
at forestry.book.BookLoader.loadCategory(BookLoader.java:168)
at forestry.book.BookLoader.loadBook(BookLoader.java:114)
at forestry.book.items.ItemForesterBook.getGui(ItemForesterBook.java:39)
at forestry.core.gui.GuiHandler.getClientGuiElement(GuiHandler.java:93)
at net.minecraftforge.fml.common.network.NetworkRegistry.getLocalGuiContainer(NetworkRegistry.java:276)
at net.minecraftforge.fml.common.network.internal.FMLNetworkHandler.openGui(FMLNetworkHandler.java:111)
at net.minecraft.entity.player.EntityPlayer.openGui(EntityPlayer.java:2550)
at forestry.core.gui.GuiHandler.openGui(GuiHandler.java:47)
at forestry.core.gui.GuiHandler.openGui(GuiHandler.java:42)
at forestry.core.items.ItemWithGui.openGui(ItemWithGui.java:41)
at forestry.book.items.ItemForesterBook.func_77659_a(ItemForesterBook.java:30)
at net.minecraft.item.ItemStack.func_77957_a(ItemStack.java:217)
at net.minecraft.client.multiplayer.PlayerControllerMP.func_187101_a(PlayerControllerMP.java:511)
at net.minecraft.client.Minecraft.func_147121_ag(Minecraft.java:1597)
at net.minecraft.client.Minecraft.func_184117_aA(Minecraft.java:2254)
at net.minecraft.client.Minecraft.func_184118_az(Minecraft.java:2020)

I forgot to add patchouli :(